This invention relates to a hydraulic pressure intensifier which receives pressure fluid from a low pressure source and increases the pressure of the fluid before delivering the fluid to a utilization device.
Lapp U.S. Pat. No. 3,952,516 discloses one type of hydraulic intensifier. In the Lapp intensifier, a hydraulic motor is driven by low pressure oil from a supply source and drives a high pressure pump which boosts the pressure of the oil and delivers the oil to the utilization device. The low pressure oil exhausted from the utilization device is returned to the supply source.
The present intensifier preferably is of the self-contained type in which a hydraulic motor drives a low pressure pump as well as a high pressure pump. The motors and pumps are encased within a housing which serves as an oil sump. The low pressure pump draws oil from the sump and delivers such oil at low pressure to the high pressure pump to charge the latter. The high pressure pump boosts the pressure of the oil and delivers the oil to the utilization device. Oil exhausted from the utilization device is returned to the sump for recirculation to the low pressure pump. In this way, the oil circulates in a closed loop between the intensifier and the utilization device and thus the circuit is not contaminated by foreign material in the low pressure fluid from the supply source.